@article{c1d3da3e141b49f89be91565a54812bb,
title = "Improved in vivo diffusion tensor imaging of human cervical spinal cord",
abstract = "We describe a cardiac gated high in-plane resolution axial human cervical spinal cord diffusion tensor imaging (DTI) protocol. Multiple steps were taken to optimize both image acquisition and image processing. The former includes slice-by-slice cardiac triggering and individually tiltable slices. The latter includes (i) iterative 2D retrospective motion correction, (ii) image intensity outlier detection to minimize the influence of physiological noise, (iii) a non-linear DTI estimation procedure incorporating non-negative eigenvalue priors, and (iv) tract-specific region-of-interest (ROI) identification based on an objective geometry reference. Using these strategies in combination, radial diffusivity (λ⊥) was reproducibly measured in white matter (WM) tracts (adjusted mean [95% confidence interval]=0.25 [0.22, 0.29] μm2/ms), lower than previously reported λ⊥ values in the in vivo human spinal cord DTI literature. Radial diffusivity and fractional anisotropy (FA) measured in WM varied from rostral to caudal as did mean translational motion, likely reflecting respiratory motion effect. Given the considerable sensitivity of DTI measurements to motion artifact, we believe outlier detection is indispensable in spinal cord diffusion imaging. We also recommend using a mixed-effects model to account for systematic measurement bias depending on cord segment.",
keywords = "Cardiac gating, Cervical spinal cord, Diffusion tensor imaging, Directional diffusivity, Lateral corticospinal tract, Non-negative eigenvalue priors, Outlier rejection, Posterior column, Reduced FOV, Reproducibility",
author = "Junqian Xu and Shimony, {Joshua S.} and Klawiter, {Eric C.} and Snyder, {Abraham Z.} and Kathryn Trinkaus and Naismith, {Robert T.} and Benzinger, {Tammie L.S.} and Cross, {Anne H.} and Song, {Sheng Kwei}",
note = "Funding Information: This work was supported by the National Institutes of Health ( P01 NS059560 to AHC, R01 NS047592 to S-KS) and the National Multiple Sclerosis Society ( RG 4009 to AHC). JX was supported by a National MS Society Postdoctoral Fellowship ( FG 1782 ). JSS was supported by National Institutes of Health ( K23 HD053212 ). ECK was supported by an American Academy of Neurology Foundation Clinical Research Training Fellowship and the National Institutes of Health ( UL1RR024992 ). RTN was supported by the National Institutes of Health ( K23 NS052430-01A1 ). TB was supported by a Bracco/American Roentgen Ray Society Scholar Award . AHC was supported in part by the Manny and Rosalyn Rosenthal–Dr John L Trotter Chair in Neuroimmunology of Barnes-Jewish Hospital Foundation . AZS was supported by P30 NS048056 . An institutional Clinical and Translational Science Award ( UL1RR024992 ) from the National Center for Research Resources (NCRR), a component of the National Institutes of Health (NIH) and NIH Roadmap for Medical Research NIH, provided funding for the Neuroclinical Research Unit where research subjects were examined. This research was also supported in part by NIH grants CO6 RR020092 and RR024992 (Washington University Institute of Clinical and Translational Sciences – Brain, Behavioral and Performance Unit). The funding source had no role in the study design or in the collection, analysis and interpretation of data. The contents of the work are solely the responsibility of the authors and do not necessarily represent the official view of NCRR or NIH. ",
year = "2013",
month = feb,
day = "5",
doi = "10.1016/j.neuroimage.2012.11.014",
language = "English",
volume = "67",
pages = "64--76",
journal = "NeuroImage",
issn = "1053-8119",
}